The `t.join` in `ThreadsWait` will re-raiseAs `thread.join` raises the exceptions that happen inexception from the thread, it will trigger a thread being waited on.exception report.

If the thread being waited on was using `report_on_exception = false`, the wait thread will report the exception and the `report_on_exception = false` effectively did nothing, as you still got an exception report.

anyway.

If the thread was using `report_on_exception = true`, both threads will report the exception, so you get it twice.exception.

I think this could be fixed by always setting `report_on_exception = false` for the wait thread.